James smith



(No Model.)

J. SMITH.

VALVE FOR STEAM ENGINES.

Patented Oct. 12, 1886.

l/mtmeowa UNITED STATES PATENT OFFICE.

J AMES SMITH, OF DRESDEN, NE\V YORK.

VALVE FOR STEAM-ENGINES.

SPECIFICATION forming part of Letters Patent No. 350,606, dated October 1.2, 1886.

' Application filed July 7, 1886. set-m1 No.207,3-16l (N0 model.)

'0 all whom it may concern.-

Be it known that I, JAMES SMITH, a citizen of the United States, residing at Dresden, in the county of Yates and State of New York, have invented a new and useful Improvement in Valves for SteamEngines, of which the following is a-specification.

My invention relates to an improvement in valves for steam engines; and it consists in the peculiar construction and combination of de vices that will be more fully set forth hereinafter, and particularly pointed out in the claims. I

In the drawings, Figurel is a side elevation of my invention, partly in section. Fig. 2 is a vertical longitudinal sectional view of the same. Fig. 3 is a transverse sectional view on line 00 m, Fig. 2.

A represents the steam-chest of the engine, which is provided with the removable top plate, B, that is secured on the upper edges of the side and end walls of the steanrchcst by means of bolts 0. In the bottom plate of the steamchest, at the center thereof, is made a transverse exhaust port, D, and on opposite sides of the said cXha-ustport are the induction-ports E and F. On the inner sides of the side walls of the steam-chest are made vertical recesses G, which extend nearly throughout the length of the steam-chest, and in the said recesses is fitted an arch-plate, H, which extends transversel y across the steam-chest and nearly from end to end thereof. The lower edges of the said arch-plate are kept in contact with the bottom plate of the steam-chest by means of setscrews I, which pass down through the top plate of the steam-chest and bear upon the central portion of the arch-plate. The under side of the arch-plate is either concave or triangular in shape, as may be preferred.

K represents a hollow valve-sleeve, which is provided with right and left hand screw threads, which meet at the center of the valve sleeve. On one end of the sleeve K is screwed a valve, L, and on the opposite end thereof is screwed a valve, M. The upper side of the said valves are adapted to the contour of the under side of the arch-plate and fit snugly therein, and the lower sides or edges of the said valve bear firmly upon the bottom plate of the steam-chest. Y

N represents a cut off-valve sleeve, which extends through the valve sleeve K and fits snugly in the said sleeve, the said valve-sleeve N having right and left hand screw-threads n and a at its opposite ends. That portion of the valve-sleeve N which passes through the sleeve K is plane. On the threaded portion a of the cutoff-valve sleeve is screwed a cut-off valve, 0, and on the threaded portion a of the said sleeve is screwed a cut-off valve, P. The said cut-ofi valves correspond with the valves L and M, and thereby bear against the under side of the arch-plate, and also against the-bottom plate of the steam-chest. On the inner side of the threaded portion a of the sleeve N is a longitudinal slot, of, and a similar slot, n is cut in the said sleeve near the opposite extremity thereof.

R represents a val.verod, which passes through the cut-ofivalve sleeve and is adapt ed to work back and forth therein, thesaid rod being secured to the said sleeve by means of pins S, which pass through openings T, that are made in the said valvc-rod and work in the slots a and a of the cut-oft valvc sleeve, thereby permitting the valve-rod to work in the cut-off-valve sleeve and independently thereof a distance corresponding to the length of the slots a and a.

One end of the cut-off-valve sleeve passes through one of the end walls of the steamchest, and the rod R has one end projecting beyond the outer end of the cut-off-valvesleeve,

and is connected to andactuated by the eocen- 8 I tric or valve gear of the steam-engine. This said eccentric or valve-gear is not here shown nor more particularly described, for the rea- "son that it is of the well-known common con struction and forms no part of my invention. 0

It will be seen that the valve-sleeve K is free to turn on the cutoff-valve sleeve, and as the said sleeve K is provided with the right and left hand screw-threads the valves L and M may be adjusted toward or from each other 5 by simply rotating the sleeve K, as will be very readily understood. The cutoff-valve sleeve N may be also turned, and thereby cause the cutoff valves 0 and P to be adjusted either toward or from each other.

The valve L slides over the induction-port E, and the valve M slides over the inductionport F.

The operation. of my invention is as follows: \Ve will assume the valves to be in their initial position, as shown in Fig. 1, when the valve M is on the outer side of the port F and the valve L is on the inner side of the port E and the cut off'valve sleeve is at the rearward limit of its movement, so as to move the valve 0 under one end of the arch-plate, the cut-off valve Pbeing moved beyond the opposite end of the arch-plate. The steam from the steamehest is admitted past the cut-off valve 1, under one end of the arch-plate, and exerts its pressure directly against the valve M. As the rod R is moved forward by the cocentric or valve gear, thevalve-sleeve K,whieh is connected to the said rod by means of the transverse pin, as hereinbefore described, will be moved forwardly with the said rod, causing the valve M to open the port F and the valve L to simultaneously close the port E. The steam then passes through the port F into the rear end of the steam-cylinder, and drives the piston forward. As the rod R continues to move forward, it gradually enlarges the uncovered portion of the port F, causing the pins S to move forward in the slots of the cut off-valve sleeve, the said eut-off'valve sleeve and valves remaining stationary until the pins S reach the front ends of the slots n andnflwhen the cutoff-valve sleeve is caused to move for ward with. the valvesleeve K and the rod It, and thus move the cutoff valve 0 from under the front end of the arclrplate and draw the cutoff valve P under the rear end of the said arch-plate, thereby cutting off the supply of steam from the port]? and permitting the cutoff valve 0 to admit steam under the front end of the arch-plate to theiiuluction-port E, when the motion of the piston will be reversed. \Vhile the piston is moving forward the dead steam in the front end of the cylinder is ex hausted through the portE to the central portion of the arch plate, between the opposing inner sides of the valves L and M, and escapes through the port D. By adapting the valves L and M to move for a slight distance independently of the cutoff valves 0 and I and by providing means for adjusting the said valves and cut-off valves toward or from each other, I am enabled to cutoff the steam at any desired portion of the stroke, and thus use the same expansively, and I am also enabled to give the valves any desired amount of dead.

The arch-plate above the valves prevents downward pressure of the steam in the steamchest upon the valves, thus permitting them to slide evenly back and forth, and reducing the stcanrpressure on the valves to a minimum, thereby increasing the power of the engine, and consequently effecting an economy of fuel and water.

As the steam bears upon the outer sides of both of the cut-off valves constantly, itwill be seen that they are effectually ba anced in the steam'ehest.

Having thus described my invention, I clai1n- 1. The combination of the valve-sleeve hav ing the valves Land M, and the cut-offivalve sleeve'or arm N,independent-ly movable in the valve-sleeve for a suitable distance, and' pro vided with the cut-off valves 0 and I, substantiall y as described.

2. The combination of the steam-chest having the induction and exhaust ports and the arch-plate H with the valvesleeve K, having the valves L and M, and the cut-off-valve sleeve N, indepcndentlymovable in the valvesleeve for a suitable distance, and provided with the cutoff valves 0 and I, substantially as described.

3. The combination of the steam-chest having the induction and exhaust ports and the areh-plateHwith thevalve-slceveK,havingthe valves L and M, adjustable toward or from each other on the said sleeve, and the cut-offvalve sleeve N ,passing through the sleeve K, and independently movable therein. for a slight distance, the said sleeve N having the cut-off valves 0 and 1 near its opposite extremity and on the outer sides of the valves, the said cut-off valves being adjustable on the cutoffl valve sleeve toward or from each other, substantiall y as described.

4. The combination of the steam-chest haw ing the induction and exhaust-ports and the arch'platc II with the sleeve K, having the valves L and M, the sleeve N, passing through the sleeve K and independently movable therein for a slight distance, the cut-off valves 0 and Rattached to the sleeve N, and the red It, extending through the sleeve N, independ' entl y movable therein for a suitable distance and connected to the sleeve K, whereby the said sleeve K and the rod R maybe moved together independently of the sleeve N, substantially as described.

5. The combination of the steam'chest hav ing the induction and exhaust ports and the arch-plate II with the valve-sleeve K, having the right and left hand screw threads, the valves L and M, secured on the said sleeve, the cutoff-valve sleeve N, extending through the sleeve K, and having the right and left hand threads a and a, and the slots a and a", the cut-off valves secured on the threaded portions of the sleeve N, the rod R,passing through thesaid sleeve, and the pins working in. the slots a and at", extending through the rod R and bearing against the ends of the sleeve K, substantially as described.

6. The combination of the steam-chest having the induction and 6X11H11Sl7 ports, and the arch-plate, with the valve stem or rod having the valves L and M, and the cut-off valves and I, which work under the arch-plate and bear directly upon the bottom plate of the steam-chest, substantially as described.

7. The combination of the steam-chest havssaece a In testimony that I claim the foregoing as my 10 own I have hereto affixed my signature in presence of two witnesses.

JAMES SMITH.

Witnesses:

SETH YOUNGS, JAMES F. REYNoLDs. 

